Unify fixers related to blank lines before namespace

[Wirone]

I think we could deprecate no_blank_lines_before_namespace and single_blank_line_before_namespace, and introduce blank_line_before_namespace with configurable strategies. This way discoverability would be better - having 2 separate fixers makes it harder to find that there are alternative options.

Related to #4897.

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FYI: Done in #7053

[keradus]

@Wirone , this decision was already made, simply execution was never prioritised.

Ultimately, all fixers that are conflicting one to another should be changed [eg combined into single rule]. You can find them here:

PHP-CS-Fixer/src/FixerFactory.php

Lines 200 to 210 in b9a9bd6

	private function getFixersConflicts(FixerInterface $fixer): ?array
	{
	static $conflictMap = [
	'no_blank_lines_before_namespace' => ['single_blank_line_before_namespace'],
	'single_import_per_statement' => ['group_import'],
	];
	$fixerName = $fixer->getName();
	return \array_key_exists($fixerName, $conflictMap) ? $conflictMap[$fixerName] : [];
	}

[Wirone]

OK, so it seems like something to do 🙂. Thanks for pointing out this place in FixerFactory.

[keradus]

simply execution was never prioritised.

OK, i will self-correct myself :D

we had gazillion of conflicting fixers in past, most of the job is done, simply some long-tail present